SWISS flight LX9 from Chicago O’Hare to Zurich diverted to Lajes Airport on the Azores island of Terceira on Tuesday morning after an unidentified pungent odour was detected in the Economy Class cabin.
The Boeing 777-300ER, registered HB-JNF, was approximately halfway across the Atlantic and cruising at 37,000 feet when the crew decided to divert. The crew declared an emergency to give the aircraft priority with air traffic control.
The aircraft landed safely on Lajes Runway 33 at around 06:30 local time and taxied from the runway under its own power. All 222 passengers and 16 crew members—two pilots and 14 cabin crew—disembarked normally.
Five passengers and one crew member were examined after briefly experiencing eye irritation, nausea or headaches. None required further medical treatment.
SWISS dispatched another Boeing 777-300ER, reportedly HB-JNK, from Zurich to collect the passengers and crew. Their replacement flight was expected to arrive in Zurich at approximately 22:15.
The deployment forced the cancellation of flight LX8 from Zurich to Chicago and the subsequent return service. SWISS said it was arranging alternative travel for affected passengers.
The cause of the odour remains unknown. Technical specialists will inspect HB-JNF, and the airline said it would not speculate until it completes its investigation. SWISS statement